Poker Chips Invisibly Change Places

Poker chips have become a popular item with present-day magicians. Here is just one of many magic tricks that can be performed with these versatile accessories.
Two poker chips, orange on either side, are placed under a canopy of like colour. Two more chips, this time green on either side, are placed under a green cover. After a time, the magician discloses that there is a chip of each colour, orange and green, under either cover. One chip from each cover has crossed over.